Pulmonary Nocardiosis Caused by Nocardia exalbida in a Patient with Lung Cancer and Radiation Pneumonitis: A Case Report and Literature Review.

We report a case of Nocardia exalbida (N.exalbida)-induced pneumonia in a 70-year old Japanese man with lung cancer and radiation pneumonitis. He initially received doripenem (1.5 g/day) for pneumonia treatment, and N.exalbida was identified by a clone library analysis of bronchoalveolar lavage fluid obtained from the pneumonia lesion. The doripenem dosage was therefore increased to 3.0 g/day with adjunctive trimethoprim/sulfamethoxazole, and his pneumonia improved. N. exalbida is susceptible to antibiotics; thus, in nocardiosis, N. exalbida infection might be associated with a good response to treatment, although its clinical findings are non-specific and similar to those of other Nocardia infections.